Study On The Preparation And Performance Of PBS-based Composites

Since the modern industrial age,serious energy crisis has occurred all over the world due to the fast development of technology and the overexploitation of petroleum resources.Meanwhile,the widespread application of traditional non-biodegradable plastics has aggravated environmental pollution on the earth.Biodegradable plastics have emerged rapidly under such circumstances in recent years.Poly(butylene succinate)(PBS)is a kind of aliphatic polyester with great potential for development on account of the excellent biodegradability and biocompatibility.However,some shortcomings are realized,such as poor toughness,slow crystallization rate and difficulty in moulding during processing,resulting its further application was limited.In this paper,PBS was blended to improve above drawbacks with two modifiers,Talc and poly(3-hydroxybutyric-co-4-hydroxybutyric acid)(P34HB),and the structure and properties of two composites,PBS/Talc and PBS/P34 HB,were systematically investigated respectively.The detailed work is as follows:1.A series of PBS/Talc composites were prepared by the means of melt blending using PBS as matrix and Talc as filler.Then,the influence of particles size and amount of Talc on mechanical properties,glass transition,crystallization process and morphology,rheological properties,thermal stability and microscopic morphology were investigated.The results showed that the impact strength of the composites reached to 88 J/m,which was improved by double relative to original PBS when the content of modified 1250 mesh Talc was 6wt%,proving that the toughness of the composites has been improved.Talc disrupted the regularity of the molecular chain of PBS.The crystallization temperature of the composites increased 86.95 °C with the decrease from 44.14% to 20.80% of the crystallinity,which was16.74 °C higher than that of original PBS.The size of PBS spherical crystals decreased,which indicated that Talc is an effective nucleating agent and can greatly improve the crystallization properties of PBS.With the increase of Talc content,the glass transition temperature of the composites increased from-23.95 °C to-19.66 °C with an increase in the initial thermal decomposition temperature of 26 °C.The storage modulus,loss modulus and complex viscosity of the composites increased,which explained the viscoelasticity of the composites was enhanced.2.Grafting modification of PBS was carried out by introducing glycidyl methacrylate(GMA).Then,PBS/P34HB(PBP)and PBS-g-GMA/P34HB(PGP)composites were prepared and the performance of composites was tested.The results showed that the compatibility between PBS and P34 HB in PGP has significantly improved,which was different from the poor compatibility between two phases in PBP.The impact strength of PGP reached to 264 J/m with 10wt% P34 HB,which was 5-fold increase compared to original PBS.When the content of P34 HB was 30wt%,the crystallization temperature of PBP and PGP increased to 78.90 °C and 87.78 °C at 30% P34 HB,which was 8.69 °C and 17.57 °C higher than that of PBS,respectively,while the crystallinity of PGP decreased from 44.14%to 20.80%.In addition,the crystalline region of PGP was a continuous phase compared with PBP.With the increase of content of P34 HB,the storage modulus,loss modulus and complex viscosity of the composites enhanced,indicating that the melt strength of composites was improved so that it was easier to mould during processing and the application of PBS was further expanded.